Human adiaspiromycosis: Cicatricial lesions in mediastinal lymph nodes

Abstract

Chest roentgenogram of a sixty-year-old male patient, revealed a tumoral mass in the right lung, that was later demonstrated by transbronchial biopsy, to be a bronchogenic adenocarcinoma. There was no tomographic evidence of distant metastasis, however, in order to assess the mediastinal involvement for staging of the tumor, biopsies from the regional lymph nodes were obtained. Microscopic examination of the sample tissues failed to show any metastatic lesion, but, unexpectedly, revealed the presence of cicatricial granulomas in an advanced stage of fibrosis. They contained a few round, empty and collapsed corpuscles, limited by a thick PAS-positive, membrane. These structures were identified as adiaconidia of Emmonsia crescens, the etiological agent of human adiaspiromycosis. In the tissue sections, a large amount of carbon dust (anthracosis) was also seen.